This invention relates to bis-platinum complexes and their use as antitumor agents in humans and animals.
It is known that Cisplatin, cis-[Pt(NH.sub.3).sub.2 Cl.sub.2 ]is effective against several types of animal tumors and has been used successfully in treating certain types of malignancies in humans. A number of other platinum complexes have been tested for antitumor activity, e.g., increased life span for mice having implanted tumors such as L-1210 lymphoid leukemia.
An oligomeric platinum complex is disclosed in U.S. Pat. No. 4,128,342 to Yolles. These complexes contain bridging halogen ligands as well as a number of platinum ions in both therapeutic and non-therapeutic forms in the complex.
Three bis-platinum complexes were reported by Rochon et al., J. Clin. Hematology & Oncology, 12, 39-43 (May, 1982). Two of those showed no activity against L-1210 lymphoid leukemia, while a third showed a low level of activity but also showed significant toxicity.
Gale et al., U.S. Pat. 4,137,248, and Kidani et al., U.S. Pat. No. 4,169,846, disclose monomeric complexes of [1,2-diaminocyclohexane]Pt (II). The disclosures of the foregoing patents are incorporated herein by reference.
A need continues to exist for platinum complexes having appreciable water solubility to facilitate intravenous injection, along with significant antitumor activity and low toxicity.